1. Field of the Invention
The present invention relates to ball joint assemblies. More particularly, the present invention relates to an economical ball joint assembly which prevents contaminants from entering the assembly.
2. Disclosure Information
In known ball joint assemblies, cover plates are typically crimped over the assembly to prevent axial movement of the joint in a housing and to prevent water or other contaminants from entering the joint and degrading its function. Typically, the cover plates are flat and are secured by crimping a lip of the joint housing over the plate. The lip extends above the plate after crimping, resulting in an area between the lip and the cover plate which collects contaminants while the joint is in use. Although a seal is provided by the cap, the contaminants still flow into the assembly, typically by capillary flow between the cover plate and the lip of the housing.
Many suggestions for preventing contamination have been proposed. For example, it is known to fill the collecting area with adhesives or liquid sealers. However, these sealers are messy, difficult to control and often wear out or do not completely prevent contaminants from flowing past them. Another proposal is taught in U.S. Pat. No. 3,695,651. The '651 patent teaches hermetically sealing a ball joint assembly by friction welding a dome-shaped cap over the end of the ball and socket assembly. The '651 patent uses a metal disk which is friction welded to a polymeric material. Although this system probably achieves the goal of completely preventing contamination of the assembly, it is expensive and difficult to implement in a production environment because of the added equipment and labor to friction weld.
Therefore, it would be desirable to provide an economical, simple solution for preventing contamination of a ball joint assembly.